<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
</head>

<body>
    <div id="app">
        {{title}}
    </div>
    <script src="vue.js"></script>
    <script>
        var vm = new Vue({
            el: "#app",
            data: {
                title: "hllowVue"
            },
            created() {
                console.log(this.$el);
            },
            mounted() {
                console.log(this.$el);;
            },
        })
        setTimeout(() => {
            vm.title = "你好 vue"
        }, 1000);
    </script>
</body>

</html>